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Commit a2bf0477 authored by Kurt Hackel's avatar Kurt Hackel Committed by Mark Fasheh
Browse files

ocfs2: mle ref counting fixes 



Signed-off-by: default avatarKurt Hackel <kurt.hackel@oracle.com>
Signed-off-by: default avatarMark Fasheh <mark.fasheh@oracle.com>
parent 95883719

fs/ocfs2/dlm/dlmmaster.c

+90 −19
Original line number Diff line number Diff line
@@ -74,6 +74,7 @@ struct dlm_master_list_entry 
	wait_queue_head_t wq;

	atomic_t woken;

	struct kref mle_refs;

	int inuse;

	unsigned long maybe_map[BITS_TO_LONGS(O2NM_MAX_NODES)];

	unsigned long vote_map[BITS_TO_LONGS(O2NM_MAX_NODES)];

	unsigned long response_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
@@ -337,6 +338,31 @@ static inline void dlm_mle_detach_hb_events(struct dlm_ctxt *dlm, 
	spin_unlock(&dlm->spinlock);

}



static void dlm_get_mle_inuse(struct dlm_master_list_entry *mle)

{

	struct dlm_ctxt *dlm;

	dlm = mle->dlm;



	assert_spin_locked(&dlm->spinlock);

	assert_spin_locked(&dlm->master_lock);

	mle->inuse++;

	kref_get(&mle->mle_refs);

}



static void dlm_put_mle_inuse(struct dlm_master_list_entry *mle)

{

	struct dlm_ctxt *dlm;

	dlm = mle->dlm;



	spin_lock(&dlm->spinlock);

	spin_lock(&dlm->master_lock);

	mle->inuse--;

	__dlm_put_mle(mle);

	spin_unlock(&dlm->master_lock);

	spin_unlock(&dlm->spinlock);



}



/* remove from list and free */

static void __dlm_put_mle(struct dlm_master_list_entry *mle)

{
@@ -390,6 +416,7 @@ static void dlm_init_mle(struct dlm_master_list_entry *mle, 
	memset(mle->response_map, 0, sizeof(mle->response_map));

	mle->master = O2NM_MAX_NODES;

	mle->new_master = O2NM_MAX_NODES;

	mle->inuse = 0;



	if (mle->type == DLM_MLE_MASTER) {

		BUG_ON(!res);
@@ -809,7 +836,7 @@ lookup: 
	 * if so, the creator of the BLOCK may try to put the last

	 * ref at this time in the assert master handler, so we

	 * need an extra one to keep from a bad ptr deref. */

	dlm_get_mle(mle);

	dlm_get_mle_inuse(mle);

	spin_unlock(&dlm->master_lock);

	spin_unlock(&dlm->spinlock);
@@ -899,7 +926,7 @@ wait: 
	dlm_mle_detach_hb_events(dlm, mle);

	dlm_put_mle(mle);

	/* put the extra ref */

	dlm_put_mle(mle);

	dlm_put_mle_inuse(mle);



wake_waiters:

	spin_lock(&res->spinlock);
@@ -1753,6 +1780,7 @@ ok: 
	if (mle) {

		int extra_ref = 0;

		int nn = -1;

		int rr, err = 0;

		

		spin_lock(&mle->spinlock);

		if (mle->type == DLM_MLE_BLOCK || mle->type == DLM_MLE_MIGRATION)
@@ -1772,27 +1800,64 @@ ok: 
		wake_up(&mle->wq);

		spin_unlock(&mle->spinlock);



		if (mle->type == DLM_MLE_MIGRATION && res) {

		if (res) {

			spin_lock(&res->spinlock);

			if (mle->type == DLM_MLE_MIGRATION) {

				mlog(0, "finishing off migration of lockres %.*s, "

			     		"from %u to %u\n",

			       		res->lockname.len, res->lockname.name,

			       		dlm->node_num, mle->new_master);

			spin_lock(&res->spinlock);

				res->state &= ~DLM_LOCK_RES_MIGRATING;

				dlm_change_lockres_owner(dlm, res, mle->new_master);

				BUG_ON(res->state & DLM_LOCK_RES_DIRTY);

			} else {

				dlm_change_lockres_owner(dlm, res, mle->master);

			}

			spin_unlock(&res->spinlock);

		}

		/* master is known, detach if not already detached */

		dlm_mle_detach_hb_events(dlm, mle);

		dlm_put_mle(mle);



		/* master is known, detach if not already detached.

		 * ensures that only one assert_master call will happen

		 * on this mle. */

		spin_lock(&dlm->spinlock);

		spin_lock(&dlm->master_lock);



		rr = atomic_read(&mle->mle_refs.refcount);

		if (mle->inuse > 0) {

			if (extra_ref && rr < 3)

				err = 1;

			else if (!extra_ref && rr < 2)

				err = 1;

		} else {

			if (extra_ref && rr < 2)

				err = 1;

			else if (!extra_ref && rr < 1)

				err = 1;

		}

		if (err) {

			mlog(ML_ERROR, "%s:%.*s: got assert master from %u "

			     "that will mess up this node, refs=%d, extra=%d, "

			     "inuse=%d\n", dlm->name, namelen, name,

			     assert->node_idx, rr, extra_ref, mle->inuse);

			dlm_print_one_mle(mle);

		}

		list_del_init(&mle->list);

		__dlm_mle_detach_hb_events(dlm, mle);

		__dlm_put_mle(mle);

		if (extra_ref) {

			/* the assert master message now balances the extra

		 	 * ref given by the master / migration request message.

		 	 * if this is the last put, it will be removed

		 	 * from the list. */

			dlm_put_mle(mle);

			__dlm_put_mle(mle);

		}

		spin_unlock(&dlm->master_lock);

		spin_unlock(&dlm->spinlock);

	} else if (res) {

		if (res->owner != assert->node_idx) {

			mlog(0, "assert_master from %u, but current "

			     "owner is %u (%.*s), no mle\n", assert->node_idx,

			     res->owner, namelen, name);

		}

	}
@@ -2138,7 +2203,7 @@ fail: 
	 * take both dlm->spinlock and dlm->master_lock */

	spin_lock(&dlm->spinlock);

	spin_lock(&dlm->master_lock);

	dlm_get_mle(mle);

	dlm_get_mle_inuse(mle);

	spin_unlock(&dlm->master_lock);

	spin_unlock(&dlm->spinlock);
@@ -2155,7 +2220,10 @@ fail: 
		/* migration failed, detach and clean up mle */

		dlm_mle_detach_hb_events(dlm, mle);

		dlm_put_mle(mle);

		dlm_put_mle(mle);

		dlm_put_mle_inuse(mle);

		spin_lock(&res->spinlock);

		res->state &= ~DLM_LOCK_RES_MIGRATING;

		spin_unlock(&res->spinlock);

		goto leave;

	}
@@ -2196,7 +2264,10 @@ fail: 
			/* migration failed, detach and clean up mle */

			dlm_mle_detach_hb_events(dlm, mle);

			dlm_put_mle(mle);

			dlm_put_mle(mle);

			dlm_put_mle_inuse(mle);

			spin_lock(&res->spinlock);

			res->state &= ~DLM_LOCK_RES_MIGRATING;

			spin_unlock(&res->spinlock);

			goto leave;

		}

		/* TODO: if node died: stop, clean up, return error */
@@ -2212,7 +2283,7 @@ fail: 


	/* master is known, detach if not already detached */

	dlm_mle_detach_hb_events(dlm, mle);

	dlm_put_mle(mle);

	dlm_put_mle_inuse(mle);

	ret = 0;



	dlm_lockres_calc_usage(dlm, res);